The 21.8 km Hamilton bypass is costing about $790,000,000 or $35,909,000 per km. This project is part of the present Government’s Roads of National Significance (RoNS), which require priority treatment to the extent that according to Waikato Regional Land Transport Strategy 2011-41 Page150:

The Waikato Expressway will account for the entire major state highway improvement budget, leaving no additional funding available for other significant improvements.

* The high investment for Roads of National Significance has and will continue to result in reduced national funding available for other activities (eg other roading routes, roading maintenance, roading renewals, passenger transport services, walking and cycling, travel demand management, safety and community programmes)

The RoNS are ‘lead infrastructure’ projects – that is, they enable economic growth rather than simply responding to it.

This means the Government is investing in infrastructure now to encourage future economic growth rather than wait until the strain on the network becomes a handbrake on progress.

One of the outcomes from building the Waikato expressway is that there will be growth in traffic volumes that would not happen if these roads were not built. We can see this from the NZTA information sheet below.

On the Hamilton Section we can see that predicted traffic between the Tamahere and Cherry Lane locations will be 40,000 vpd if the bypass is built: an increase of 16,000 vpd over the 2013 count of 24,000 vpd. Some of this new traffic could be coming from SH29 & SH1b which in 2013 both carried about 3,000 vpd each.

If the above information is correct this suggests a 30-65% change over the next 7 years. That is 30% if SH29 & SH1b were closed to through traffic, plus 35% from new encouraged future economic growth, or 65% all from new future economic growth.

The above illustration of the Tamahere Section shows predicted traffic between Tamahere and Cherry Lane (A) will be 32,600 vpd if the bypass is not built. This represents an increase of 8,600 vpd over the 2013 count of 24,000 vpd. This represents a 35% (4%-5% per year) increase in “future economic growth” over the next 7 years without the need for new road building, making $790,000,000 of funding available for other significant improvements.

Lastly here is a very boring graph from Waikato District council integrated Land transport strategy draft report, page 23 showing state highway flows in the Waikato.